876 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY IV. 
Oil page 37. The Ehinohatidcc are all ovoviviparous, a character 
which distiug'uishes them from the oviiiarous Raiidce. 
On page 38. EM/iohatus leticorJiynclnts Giiiither is not identical' with 
JR. product and should he erased from the synonymy of the latter 
species, which does not extend southward from California. In R. pro- 
ductus the rostral ridges are armed with small spines above, and are 
largely confluent anteriorly, not “separated along their entire length,’^ 
as stated in the text; anterior nasal valve not dilated laterally and not 
extending to the inner edge of the nostril; first dorsal well behind 
tips of ventrals, not reaching nearly to the second. Females with a 
small digitate flap, free behind, above tip of snout. Color grayish, 
without pale si)ots; snout i)aler, a black blotch beneath it. San Fran- 
cisco to San Diego. The description quoted in the text, from Dr. 
Streets, was taken from a si)ecimen of R. leucorliynchus. R. jJroducius 
and R. lentiginosus belong to the subgenus Rhinohatus, distinguished 
from Syrrhina^’ by the long, sharp snout and narrow nasal flaps. Our 
two species of Syrrhitia"'^ have each recently been made the tyi)es of 
new generic names, viz: Zapteryx^' (Jor. & Gilb. Proc. U. S. Nat. Mus. 
1880, 53: type Plafyrhina exasperata J. & G.) and Platyrhinoidis‘' (Gar- 
man, Proc. U. S. Nat. Mus. 1880, 522: type Platyrhina triseriata J. & G.). 
PlatyrMnoidis is “distinguished from ^yrrliina and Tryonorhina by the 
labial fold, nasal valves, and marginal series of si)ines, and from Platyr- 
Mna by the fold, valves, separation of pectorals, and viviparity.” Trygo- 
norliina alreata Garman, Bull. Mus. Comi). Zool. 1880, ICO, is identical 
with Rhinohatus exasperatus. 
In R. exasperatus WiQ dorsals are well forward, the origin of first dorsal 
being nearer hinder part of root of ventrals than front of second dorsal. 
In R. triseriatus the origin of first dorsal is nearer root of caudal than 
the hinder part of root of ventrals. In the latter the rostral ridges are 
strongly convergent, in R. exasperatus they are parallel. 
On page 39, add to description of 47, Torpedo calif ornica Ayres: 
Color very dark brown, with small round black spots, which are some- 
times obsolete. Eyes small, the spiracles at a distance behind them 
more than twice diameter of eye and more than length of sinracle; edges 
of spiracles not fringed; breadth of mouth about equal to its distance 
from tip of snout. Teeth small, sharp, in few series. Tail a little 
shorter than disk. First dorsal fin more than twice as large as second ; 
half of it opposed to the ventrals. Coast of California; thus far seen 
only about San Francisco and Santa Cruz. 
